Portugal began filling a vast hydroelectric dam on Friday which will irrigate the country's scorched south, but submerge 160 rocks covered with Stone Age drawings and flood habitats for rare flora and fauna.

Alqueva's victims include:

Bats

Imperial eagles

Iberian lynx

Black storks

A rare Narcissus

Wild boar

The Alqueva dam in Alentejo, which will create Europe's largest artificial lake, was first mooted in 1957 under the dictatorship of Antonio de Oliveira Salazar and has cost $1.7bn.

Around 30 environmental protesters dressed in mourning and carrying a wooden white elephant protested at the site, the French news agency, AFP, reported.

They are concerned at the destruction of habitat for rare species, including eagles, kites, wild boars, and the Iberian lynx.

Job creation

But politicians across Portugal's political spectrum insist the project is necessary to help feed the country's poorest mainland region.

"The species that is disappearing from the Alentejo is man," said Jose Carreira Marcos, the major of a large rural community in nearby Beja.

"This is a chance to change that. We have the sun, we have the land, and now we have the water."

The government has built a replica of the village of Luz - which means "light" in Portuguese - two miles away on the future banks of the reservoir but there has been no date set for moving the residents.

Uprooted

Many of the inhabitants, whose families have lived in the village for generations, are reluctant to move.

The village of Luz has been replicated nearby

"I will cry when I have to leave. I love this place. My husband, my parents and my grandparents all lived and died here. Why should I want to go?" 69-year-old Francina Goudino was quoted as saying.

Her relatives' graves have already been exhumed and moved.

More than 1m trees, many of them cork oaks, were felled during construction.

One of Portugal's largest green groups, Quercus, campaigned for the dam to be filled to 139 metres (457 feet), rather than its maximum depth of 152 metres to save many of the trees.

Archaeologists have encased in concrete a Roman fort, which will also be submerged.

'White elephant'

The company set up to run the reservoir says it has reconstructed bat caves and transplanted the rare narcissi threatened by the dam.

But one environmental leader, Jose Paulo Martins, says the dam is a waste of money.

"The government's own secret reports say only 48% of the irrigated land can be worked profitably," he said.